* test(vcr): guard leaked cassette patches and make injected-transport embedding tests immune
* test(vcr): derive the leak guard's patch points from vcrpy's own reset list
* test(vcr): share CapturingTransport and switch the encoding_format embedding test to it
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Co-authored-by: mateo-berri <277851410+mateo-berri@users.noreply.github.com>
